FR3119650A1 - Clamp having a retainer and a hook - Google Patents

Abstract

Clamp having a retainer and a hook Clamp (1) comprising a belt (10) carrying a retainer (12) and a hook (14) configured to hook onto the retainer to define a clamped clamping state of the clamp. The hook has a front wall (14A) and a running part (14B) which connects the front wall to the belt. The retaining member (12) carries a first abutment member (22) capable, when the hook is attached to the retaining member, of coming into abutment with a second abutment member (24) to define a position maximum projection of the hook relative to the retainer. The belt (10) has at least one abutment wall element (11A) which has the second abutment member (24). The second abutment member is located, forwards in the direction (F14) of movement of the hook towards the ear, at most in the area where the belt (10) connects to the hook (14). [Fig. 2]

Description

Clamp having a retainer and a hook

This presentation relates to a clamp, in particular a clamp of the type comprising a belt carrying a retaining member and a hook configured to hook onto the retaining member to define a clamped clamping state of the collar.

Clamps of this type are well known, for example from patent applications EP 2 480 355, EP 0 627 591 or even US 5 353 478.

They serve in particular to tighten an object, for example to connect this object to another object. For example, the other object may be a tube made of a material such as metal, and the object connected to it is a pipe, which is fitted onto the tube.

According to another example, the clamped object is formed by the ends of two tubes connected axially. For example, the tubes may be made of metal and have, at their ends, bearing surfaces projecting radially on the outer peripheries of the tubes, these bearing surfaces together forming a bulge when the tubes are butted. The belt of the collar may have a recess which accommodates this bulge. For clamping, the tubes are butted and the collar is placed around their bearing surfaces so that these can be received in the recess. The bearing surfaces and the recess can be shaped so as to bring the bearing surfaces closer together when the belt is tightened. For this purpose, the recess of the collar may have a V-shaped or U-shaped section with legs (forming the sides of the belt) folded down towards the axis of the belt and slightly inclined with respect to a plane perpendicular to this axis, in going away from each other towards their free ends close to the axis, and the bearing surfaces of the tubes can be inclined in the same way, so that the reduction in the diameter of the belt due to the tightening the collar brings the bearing surfaces closer to each other.

These clamps are generally satisfactory in many applications. However, for certain demanding applications, in particular when the clamped object is hard, the closure of the clamp can temporarily cause excessive tightening, which could adversely affect the performance of the clamp. This may, for example, be the case when the collar is used to clamp a pipe made of a hard material such as rigid plastic or metal to a fitting, or when the tube is used to connect two metal tubes axially, in particular by clamping them by their ends. metal support surfaces.

If the tightening of the collar on the tight object is temporarily too intense, it may happen that certain parts of the collar, in particular the hook, undergo plastic deformations, that is to say not reversible, or that the object tightened undergoes plastic deformations or damages such as microcracks.

These phenomena, sometimes undetectable at the time of tightening, can affect tightening performance over time. For example, when the clamp is used to connect a fluid line to a fitting or to connect two tubes for fluid, it may happen that the tightness of the assembly is no longer ensured.

The document FR2705410 attempts to propose a solution to this problem by providing that the retainer be provided with an abutment capable of coming into abutment with the internal face of the hook when the hook is hooked behind the retainer. Thus, when tightening the collar, the hook is moved so that the front wall of the hook is advanced on the retaining member until it exceeds a retaining surface of the retaining member in order to be able to hook onto this surface, at the rear of the retainer. When the hook is sufficiently advanced to allow this hooking, the stops come into cooperation, in order to prevent the hook from advancing any further.

This solution can be effective, but it can be difficult to ensure a good quality and reliable abutment contact between the abutment and the internal face of the hook. If the clamping forces involved are high, this contact may be unstable and the inner face of the hook may then act as a sliding ramp for the stopper without actually retaining it. In addition, the abutment contact may tend to oppose the slight inward radial tilting of the hook which, once the front wall of the hook has passed the first abutment member, is necessary for retaining the hooked hook behind the retainer. Thus, this solution can interfere with the attachment of the hook to the retainer.

The present presentation aims to remedy at least in part the aforementioned drawbacks by making sure to avoid, or at least to limit, the risks of over-tightening, in particular when hooking the hook on the retaining member in substantially exempting itself from the disadvantages of the aforementioned solution.

Thus, the presentation relates to a clamping collar comprising a belt carrying a retaining member and a hook configured to hook onto the retaining member to define a clamped clamping state of the collar, the hook having a front wall and a running part that connects the front wall to the belt. The retaining member carries a first abutment member capable, when the hook is attached to the retaining member, of coming into abutment with a second abutment member to define a maximum advanced position of the hook relative to the retainer. The belt has at least one abutment wall element which has the second abutment member, and this second abutment member is located, forwards in the direction of movement of the hook towards the ear, at most in the zone connecting the belt to the hook.

Thus, it is avoided to advance the hook excessively during its attachment, which makes it possible to avoid excessive tightening during this attachment. The integrity of the hook is therefore preserved by preventing it from being plastically deformed due to a momentarily excessive effort during the attachment used to tighten the collar. At the same time, the collar being designed to be tightened on an object having a certain diameter, this object is not over-tightened, by the fact that the coming into abutment of the first and second abutment members corresponds to the specification diameter of the collar , which is predefined.

The abutment contact between the first and second abutment members is made on the outside of the hook, in particular at the rear of the latter, due to the location of the second abutment member. Thus, this contact does not concern the hook and does not risk upsetting its tilting necessary for its attachment to the retainer. There is also no risk of it being damaged or lost due to the forces exerted on the hook, so that the risks of slipping are eliminated or at least considerably reduced.

Optionally, the first and second abutment members each have a first and a second abutment contact surface located on either side of a diametral plane of the belt, perpendicular to the axis of the latter.

Optionally, the belt comprises at least one sidewall which extends radially inward, the abutment wall element being formed in the sidewall.

Optionally, the belt has a recess delimited by two flanks which extend radially inwards, the abutment wall element comprising two portions of abutment wall elements, respectively formed in each of these two flanks.

Optionally, said at least one flank is interrupted at the end of the belt which carries the hook so as to present an edge portion, and the second abutment member is formed on the edge portion.

Optionally, the side is interrupted by a bend or a cut.

Optionally, the retaining member has an extension which, in the hooked state, extends under the running part of the hook and which has the first abutment member.

Optionally, the extension has a stiffening relief.

Optionally, the retaining member comprises an external radial projection.

It is understood that the first and second abutment members can thus be made in an extremely simple manner while fulfilling their function of defining the maximum advanced position of the hook relative to the retaining member when the hook is attached to the retaining member and, more precisely, at the moment when the front wall of the hook passes behind the retaining member in order to hook onto the latter, without risk of sliding between the abutment members and without interfering with the tilting of the hook required for hanging. The collar is in particular made of metal, optionally in one piece, and the first and second abutment members can be made by simple bending, cutting and/or stamping in the metallic material of the collar.

Other characteristics and advantages of the object of this presentation will emerge from the following description of embodiments, given by way of non-limiting examples, with reference to the appended figures.

Figure 1 shows, in side elevation, a clamp according to the present disclosure, ready to be closed and tightened on an object.

Figure 2 shows the collar at the time of its tightening on the object.

Figure 2A is a view of detail II of Figure 2, also in side elevation.

Figure 2B is a view of detail II, seen in perspective taken from below, according to the arrow IIB of Figure 2.

Figure 2C is a plan view of detail II seen from below, according to the arrow IIB of Figure 2.

Figure 3 is a view of the collar of the , in perspective taken from above. .

Figure 4 is a view similar to , showing a variant.

Figure 4A is a view of detail IV of the , in side elevation.

Figure 4B is a view of detail IV, in perspective taken from below, along the arrow IVB in Figure 4.

Figure 4C is a plan view of detail IV seen from below, according to the arrow IVB in Figure 4.

There is a view of the collar of the , in perspective taken from above.

detailed description

Figures 1, 2, 2A-2C and 3 are first described.

Figure 1 shows a clamp 1 comprising a belt 10 having two ends, respectively 10A and 10B. End 10A carries a retainer 12, while end 10B carries a hook 14 that is configured to hook onto retainer 12 to define a clamped clamping state of the collar shown in Figure 2. In this case, the retainer 12 projects radially outwards relative to the outer periphery of the belt 10. In this case, it is a double fold formed outwards.

Generally, in the tightened state of the collar, the belt 10 defines a circle of axis A, this axis being defined as being the axis of the clamp or the axis of its belt.

Within the meaning of this presentation, the direction going outwards or upwards is defined as being the direction going away from this axis A. Conversely, the direction inwards or downwards is that which goes by approaching this axis A. Furthermore, it is understood that, to hook onto the retaining member, the hook 14 is moved in the direction of the arrow F14. Thus, by focusing on the hook, it will be considered that the forward direction is that defined by this arrow F14. In general, looking at the hook 14 or the end 10B of the belt, the forward direction is that which goes towards the retainer 12 and the end 10A without passing through the belt. Similarly, when hooking, the retainer 12 is moved towards the hook in the direction F12. Thus, by focusing on the retaining member 12 and the end 10A of the belt, the forward direction is defined as being that which goes towards the end 10B of the hook 14 without passing through the belt 10 .

The hook 14 has a front wall 14A and a running part 14B which connects the front wall 14A to the belt 10. In the tightened state of the collar, the front wall 14A is retained behind the retaining member 12, while a front part of retainer 12 is located under running part 14B of hook 14.

In this case, the hook 14 is of the type described in French patent application No. FR 19 10485 in the name of the applicant, to which reference may be made. In particular, the running part 14B of the hook has a gripping surface 16 projecting radially outwards and two lateral edges 16A, 16B (see ) which extend axially on either side of the gripping surface while being set back radially with respect thereto. Here, axially is understood as being in the direction defined by the axis A. This gripping surface 16 is formed at the rear of a boss 16' of the running part 14B of the hook. The front wall 14A of the hook has at least one, in this case two, stiffening ribs 15.

Thus, in the example shown, the running part 14B of the hook defines a substantially rectilinear general direction D, inclined at an angle α with respect to the tangential direction T of the belt at the connection of the hook to the end 10B of the belt (see ). This angle α is for example of the order of 10 to 40 degrees, in particular of the order of 20 to 30 degrees. Note that the running part of the hook is connected to the end 10B of the belt without folding, in particular without jumping.

However, this presentation may relate to other types of hooks, in particular a hook whose running part is defined by an outward radial undulation and/or whose connection zone at the end 10B of the belt is defined by a radial outward fold, for example as in US Patent 5,353,478.

In Figure 1, we see the collar 1 during its tightening on an object 2 shown in broken lines. For example, this object 2 is the assembly of two ends of tubes connected axially. The collar 1 is tightened using a tightening tool, in particular a clamp, of which we see two jaws respectively M1, which comes into engagement behind the retaining member 12 and M2, which comes into engagement on the hook 14, in this case behind its grip surface 16.

According to the description, the retaining member 12 carries a first abutment member 22 which, as seen in Figures 2, 2A and 2B, comes into abutment against a second abutment member 24 when the hook 14 is attached. on the retainer 12 to define a maximum forward position of the hook relative to the retainer 12.

In this regard, it is noted that Figure 2 shows the collar just at the time of attachment, when the front wall of the hook 14 passes behind the retaining member 12. While the abutment members 22 and 24 are in abutment, a very slight space indicated by a clearance j may exist at the rear of the retainer 12, between the rear wall of this retainer 12 and the internal face of the front wall 14A of the hook. It is understood that the abutment of the abutment members 22 and 24 defines the maximum forward position of the hook 14 relative to the retaining member 12.

It can be seen from the figures that, in this case, the first abutment member is formed on an extension 12A of the retaining member 12 which extends forwards relative to this retaining member 12 and which, the hooked state, extends under the running part 14B of the hook. It can be seen in particular in FIG. 2B that this extension 12A can be connected to the radially projecting part of the retaining member 12 by one or more stiffening elements, such as a hardening 13 forming a recess on the inside and a boss on the outside. In general, this work hardening forms a projecting stiffening relief either on the internal face or on the external face of the extension 12A.

The retaining member 12 is formed in this case by a double radial pleat with a rear pleat portion 12′ connected to the end 10A of the waistband a front pleat portion 12″ which carries the extension 12A (see ). The stiffening relief 13 is formed at the junction between the front ply portion 12'' and the extension 12A. The extension is offset radially inwards relative to the top of the retainer 12, extending for example substantially in the extension of the peripheral direction of the belt 10. Thus, the extension 12A can extend substantially in the circumferential direction of the belt, beyond the retainer 12 going towards the front of this retainer. Thus, as can be understood in particular in FIG. 2A, in the tight state of the collar, the internal face of the extension 12A extends substantially circumferentially in the extension of the internal face of the belt. It is also possible for the extension to be substantially plane and to extend substantially tangentially to the circumferential direction of the belt, with respect to the junction zone of the retainer 12 at the end 10A of the belt.

The second abutment member 24 is for its part located in the belt 10, in particular, in the zone of connection of the end 10B of the belt to the hook 14. Thus, as can be seen in FIG. 2A, this second member stop 24 is located at the end 10B of the belt, in its transition zone with the running part 14B of the hook.

In this case, the collar shown is of the type whose belt has a recess. Indeed, this belt 10 has at least one side 11A which extends inwards. In this case, the belt has two sides, respectively 11A and 11C which extend on either side of a cylindrical central region 11B (see ). Thus, the belt generally has a U-shaped or V-shaped radial section, with a top part 11B, which forms the base of the U or the tip of the V and whose internal periphery defines the maximum internal diameter of the belt, and with two wings respectively defining two sides 11A and 11C. This top part 11B forms a central region, between the two sides 11A and 11C. Indeed, the object 2 clamped by the collar may have a radial bulge, for example formed by the bearing surfaces of two tubes connected axially, received in the internal recess of the belt delimited between the sides 11A and 11C. Thus, when it is indicated that the extension 12A of the retainer 12 extends in the extension of the periphery of the belt, it is in fact considered that it extends in the extension of the top part 11B of the belt section.

At the first end 10A of the belt, the flanks 11A and 11C are straightened radially to come substantially into the cylindrical surface defined by the central region 11B and form the retaining member 12 by folding. Similarly, at the second end 10B of the belt, the flanks 11A and 11C are straightened and it can be seen that the running part 14B of the hook has no flanks, the continuity of the material of these then being located in the direction general circumferential defined by this running part 14B. Thus, at the end 10B of the belt, the sides 11A and 11C are interrupted and have edge portions oriented towards the front of the hook 14.

The second abutment member 24 is formed in these edge portions of the flanks 11A and 11C. These flanks form abutment wall elements which, at the end 10B of the belt, form the second abutment member 24. More specifically, the second abutment member 24 is made in the edge portions of these flanks which form a transition zone between these sides and the hook. Thus, in this case, the second abutment member 24 is formed from the edge portions of the two flanks 11A and 11C which extend, in the connection zone of the hook to the end 10B of the belt, on both sides. the other of an axially median part of this connection zone.

It is understood that the second abutment member comprises two parts, respectively located in the edge portions of each of the two sides 11A and 11C. More specifically, as seen in Figures 2B and 2C, the first and second abutment members 22 and 24 each have a first and a second abutment contact surface Z1, Z2, which are located on either side of the median diametral plane P of the belt, perpendicular to its axis 1. The collie is moreover symmetrical with respect to this plane P.

Thus, the abutment contact is distributed on either side of the plane P. It opposes tilting with respect to this plane and therefore operates correctly, even if the tightening tool is imperfectly positioned with respect to the hook and retainer.

Being formed in the flanks, which are areas in which the material is highly hardened, the second abutment member is particularly resistant to clamping forces.

This is all the more true when the second abutment member is formed in the edge portions of the sidewalls which are bent to bring the material of the sidewalls into the plane of the central region 11B, these portions then being particularly hard-worked. Moreover, these edge portions are perfectly delimited and therefore allow precision abutment contact.

In this case, the collar has capacity reserves formed by zones 18 of the belt located between regions 17 in which the sides 11A and 11C are locally interrupted. Zones 18 forming reserve capacity can have increased deformability, for example by having holes 18A or the like. From this point of view, the collar can be made as described in French patent application No. 19 10486, to which reference can be made.

We will now describe Figures 4, 4A-4C and 5 which show a variant which differs from the collar which has just been described only by the conformation of the second abutment member. Thus, the same numerical references as in FIGS. 1, 2, 2A-2C and 3 are used in these figures with the exception of those which designate the second abutment member.

In figures 1, 2, 2A-2C and 3, the flanks are interrupted at the end 10B of the belt by folds which straighten them in the plane of the central region 11B.

In the variant of Figures 4, 4A-4C and 5, the sides 11A and 11C are interrupted by cutouts. Thus, the edge portions in which the second abutment member 124 is formed are the cutting edges of the sidewalls, which are oriented substantially radially. As seen in Figures 4B and 4C, the collar is symmetrical relative to the diametral median plane P, which is perpendicular to the axis A of the belt, and the abutment contacts between the first and second abutment members 22 and 124 are made on either side of the plane P.

The cutouts of the sides 11A and 11C at the end 10B of the belt result in the belt being attached to the hook only by the central region 11B. However, from its rear end 114C thus attached to the belt, the hook can have a width (measured axially) which increases so that, in its front part 14A, the hook benefits from the full width of the band in which the collar is formed. This is shown in particular by the . We also see that, at the end 10A of the belt, the sides are brought into the same plane to form the retainer, as in the previous embodiment. Of course, however, the flanks could also be interrupted by cutting in this region.

The second abutment member is particularly resistant to clamping forces because it is formed on the edges of the cutouts, which are generally oriented radially and therefore provide clean bearing surfaces that are difficult to deform. In addition, the positioning of the second abutment member is particularly precise.

Claims (9)

Clamp (1) comprising a belt (10) carrying a retaining member (12) and a hook (14) configured to hook onto the retaining member (12) to define a clamped clamping state of the collar, the hook (14) having a front wall (14A) and a running part (14B) which connects the front wall to the belt (10), the retaining member (12) carrying a first abutment member (22) suitable, when hooking the hook on the retaining member, to come into abutment with a second abutment member (24,34,44) to define a maximum advanced position of the hook (14) relative to the retaining member (12), characterized in that the belt (10) has at least one abutment wall element (11A, 11C) which has the second abutment member (24), and in that the second abutment member is located, forwards in the direction (F14) of the movement of the hook towards the ear, at most in the zone of connection of the belt (10) to the hook (14). Clamp according to Claim 1, in which the first and second abutment members (22, 24) each have a first and a second abutment contact surface (Z1, Z2) located on either side of a plane (P) diametral of the belt, perpendicular to the axis of the latter. A clamp according to claim 1 or 2, wherein the belt (10) comprises at least one flank (11A, 11C) which extends radially inward, the abutment wall member being formed in the flank. Clamp according to Claim 3, in which the belt (10) has a recess delimited by two flanks (11A, 11C) which extend radially inwards, the abutment wall element comprising two portions of abutment wall, respectively formed in each of these two flanks. Clamp according to Claim 3 or 4, in which the said at least one flank (11A, 11C) is interrupted at the end (10B) of the belt (10) which carries the hook (14) so as to present a portion edge, and wherein the second abutment member (24) is formed on the edge portion. A clamp according to claim 5, wherein the flank (11A, 11C) is interrupted by folding or cutting. Clamp according to one of Claims 1 to 6, in which the retaining member (12) has an extension (12A) which, in the hooked state, extends under the running part (14B) of the hook ( 14) and which has the first abutment member (22). Clamp according to Claim 7, in which the extension (12A) has a stiffening relief 13. Clamp according to one of Claims 1 to 8, in which the retaining member (12) comprises an external radial projection.